Support chomping of @SuppressWarnings

Closes gh-33

Author: philwebb

README.adoc

@@ -355,7 +355,7 @@ The attribute value is a space delimited list containing one or more of the foll
 | Flag | Description
 
 | `default`
-| `tags` `formatters`
+| `tags` `formatters` `suppresswarnings`
 
 | `all`
 | Enable all chomping
@@ -371,6 +371,12 @@ The attribute value is a space delimited list containing one or more of the foll
 
 | `tags`
 | Chomp on the comment tags listed above
+
+| `formatters`
+| Chomp any `@formatter:on`/`@formatter:off` comments
+
+| `suppresswarnings`
+| Chomp any `@SuppressWarnings` annotations
 |===
 
 You can prefix the flag with `+` or `-` at the block level if you want to override a document setting.

src/main/java/io/spring/asciidoctor/backend/codetools/ChompListingContentConverter.java

@@ -52,6 +52,9 @@ public String convert(Block listingBlock, String content) {
 			if (options.has(ChompOption.FORMATTERS)) {
 				chompers.add(new FormatterChomper());
 			}
+			if (options.has(ChompOption.SUPPRESSWARNINGS)) {
+				chompers.add(new SuppressWarningsChomper());
+			}
 			return chomp(content, chompers);
 		}
 		return content;
@@ -177,4 +180,22 @@ public String chomp(String content) {
 
 	}
 
+	private static class SuppressWarningsChomper implements Chomper {
+
+		@Override
+		public String chomp(String content) {
+			StringBuilder result = new StringBuilder(content.length());
+			String[] lines = content.split("\n");
+			for (String line : lines) {
+				String updatedline = line.replaceAll("@SuppressWarnings\\(.*\\)", "");
+				if (updatedline.equals(line) || !updatedline.trim().isEmpty()) {
+					result.append(updatedline);
+					result.append("\n");
+				}
+			}
+			return result.toString();
+		}
+
+	}
+
 }

src/main/java/io/spring/asciidoctor/backend/codetools/ChompOption.java

@@ -41,8 +41,13 @@ enum ChompOption {
 	/**
 	 * Chomp and formatter on/off comments.
 	 */
-	FORMATTERS;
+	FORMATTERS,
 
-	static final ChompOption[] DEFAULTS = { TAGS };
+	/**
+	 * Chomp {@code @SuppressWarnings} annotation.
+	 */
+	SUPPRESSWARNINGS;
+
+	static final ChompOption[] DEFAULTS = { TAGS, FORMATTERS, SUPPRESSWARNINGS };
 
 }

src/test/java/io/spring/asciidoctor/backend/codetools/ChompListingContentConverterTests.java

@@ -92,6 +92,11 @@ void convertWhenMethodFormattersChompReturnsChompedLines(ConvertedHtml html, Exp
 		assertThat(html.getElementHtml("code")).satisfies(expected);
 	}
 
+	@Test
+	void convertWhenSuppressWarningsChompReturnsChompedLines(ConvertedHtml html, ExpectedHtml expected) {
+		assertThat(html.getElementHtml("code")).satisfies(expected);
+	}
+
 	@Test
 	void convertWhenMultipleChompsReturnsChompedLines(ConvertedHtml html, ExpectedHtml expected) {
 		assertThat(html.getElementHtml("code")).satisfies(expected);

src/test/resources/io/spring/asciidoctor/backend/codetools/ChompListingContentConverterTests_convertWhenSuppressWarningsChompReturnsChompedLines.adoc

@@ -0,0 +1,12 @@
+= Test Document
+:chomp: suppresswarnings
+
+[source,java]
+----
+public class Example {
+
+	@SuppressWarnings("unused")
+	private String field;
+
+}
+----

src/test/resources/io/spring/asciidoctor/backend/codetools/ChompListingContentConverterTests_convertWhenSuppressWarningsChompReturnsChompedLines_expected.html

@@ -0,0 +1,5 @@
+public class Example {
+
+	private String field;
+
+}